winspool.drv: Make some functions static.

dlls/winspool.drv/info.c

@@ -7632,7 +7632,7 @@ static BOOL schedule_cups(LPCWSTR printer_name, LPCWSTR filename, LPCWSTR docume
     }
 }
 
-INT_PTR CALLBACK file_dlg_proc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)
+static INT_PTR CALLBACK file_dlg_proc(HWND hwnd, UINT msg, WPARAM wparam, LPARAM lparam)
 {
     LPWSTR filename;
 

dlls/winspool.drv/wspool.c

@@ -108,7 +108,7 @@ BOOL load_backend(void)
  * unload_backend [internal]
  *
  */
-void unload_backend(void)
+static void unload_backend(void)
 {
     EnterCriticalSection(&backend_cs);
     backend = NULL;